Field of the Invention
The present invention relates to land grid arrays used to accommodate surface mount components and devices.
Background of the Related Art
A land grid array (LGA) is a physical and electrical structure on a printed circuit board that is adapted to receive a surface mount component or device, such as an integrated circuit. The land grid array includes a large number of pads that make electrical contact with pins, balls or other conductive structures of the surface mount component or device. Each pad is also in electrical communication with a conductive pathway, such as a conductive via and/or trace that leads to some other device or feature in or on the printed circuit board.
The performance of a surface mount component or device is dependent upon good electrical contact with each of the pads in the land grid array. However, the large number of contacts makes it imperative to manufacture the surface mount component or device and the land grid array to specific tolerances. Accordingly, it is desirable to provide a land grid array where the contact surfaces of the pads lie in a plane (i.e., a high degree of flatness). Unfortunately, other components, structures and feature of the printed circuit board may adversely affect the flatness of the printed circuit board upon which the land grid array is formed.